Battle of Jizhou

The Battle of Jizhou occurred in 203 AD during the succession war between Yuan Shao's sons Yuan Shang and Yuan Tan. Cao Cao intervened after Yuan Tan asked for his aid in defeating his brother, and Cao Cao succeeded in conquering Ji Province and becoming its official Protector.

Background
Upon his death in 202 AD, Yuan Shao chose his youngest and favorite son Yuan Shang as his successor, passing over Yuan Tan and Yuan Xi. After the defeat by Cao Cao at the Battle of Liyang, the brothers began to plot against each other, with Guo Tu and Xin Ping advising Yuan Tan to invite Yuan Shang and his strategist Shen Pei to a banquet, where he could then slay them. However, Shen Pei saw through the plot and advised Yuan Shang to strike first, and he rode out to battle with 50,000 troops to face his brother Yuan Tan.

Battle between the brothers
Yuan Tan taunted Yuan Shang by accusing him of poisoning their father and usurping the succession, and, when battle was met, Yuan Shang himself charged into the fray. He drove his brother off the field and back to Pingyuan as Yuan Shang settled in Jizhou, but Yuan Tan and Guo Tu decided on a new attack led by Cen Bi. Cen Bi rode out to challenge one of Yuan Shang's champions, so Yuan Shang sent out Lu Kuang, who slew Cen Bi after a few bouts. Shen Pei then urged Yuan Shang to press the advantage, and Yuan Tan was driven into Pingyuan and besieged on three sides. Yuan Tan was then forced to send Xin Pi to Cao Cao to ask for his assistance against Yuan Shang, and Cao Cao decided to withdraw from his campaign against Liu Biao to assist Yuan Tan in crushing Yuan Shang and taking Ji Province. Yuan Shang hastily led his army back to Yejun, with Lu Xiang and Lu Kuang leading his rearguard. They attacked Yuan Tan as he pursued them, but Yuan Tan persuaded them to defect to him and Cao Cao. Cao Cao had his daughter marry Yuan Tan and made Lu Xiang and Lu Kuang generals, and he then planned an attack on Jizhou itself.

Cao Cao's intervention
Yuan Shang sent letters to the Commander of Wuan Yin Kai and Ju Shou's son Ju Gu and asked them to maintain Handan as a distant auxiliary, and Yuan Shang left Shen Pei and Chen Lin in charge of Yejun as he marched on Pingyuan with Ma Yan and Zhang Zi. Cao Cao sent Cao Hong to take Yejun as he led another army against Yin Kai at Maocheng, and Xu Chu slew Yin Kai and incorporated his troops into his army, while Zhang Liao killed Ju Gu with an arrow as he fled. Cao Cao then besieged Yejun, where the gate commander Feng Li defected to the besiegers after being punished for his drunkenness. Feng Li was given 300 troops to tunnel under one of the gates, but Shen Pei detected his ruse and filled the tunnel with rocks, killing all of the soldiers. Ma Yan then masterminded a surprise attack on Cao Cao's camp, while Li Mu planned for the garrison of Jizhou to sortie as old people, feeble soldiers, and women came out of the city to surrender. Cao Cao predicted that the soldiers would follow the civilians, and Zhang Liao and Xu Huang ambushed the soldiers as they rushed out of the city. Cao Cao then attacked Yuan Shang's camp, and he persuaded Ma Yan and Zhang Zi to defect to him. The Lu brothers, Ma Yan, and Zhang Zi were sent to seize Yuan Shang's supplies, and Yuan Shang himself was ambushed and defeated.

Fall of Jizhou
Yuan Shang fled to the Zhongshan Mountains as his camp was plundered, and Cao Cao then prepared a flood attack on the city. Shen Pei had Xin Pi's 80 family members within Jizhou executed and their heads thrown down from the walls in revenge for Xin Pi's defection to Cao Cao, and Shen Pei's nephew Shen Rong, a close friend of Xin Pi, was distressed and decided to open the gates for the besiegers. Shen Pei was captured by Xu Huang and was put to death after taunting Xin Pi and Cao Cao, and Cao Cao then entered the city of Yejun.

Aftermath
Cao Cao then spared the captured general Chen Lin and gave him a civil post, as he was impressed with his intellect. He then had his son Cao Pi marry Zhen Ji, the former wife of Yuan Xi, who had been captured while staying behind as her husband fled north. Cao Cao also formally assumed the title Protector of Ji Province, and he made sacrifices at Yuan Shao's grave and exempted his new subjects from taxes, taking their suffering into account. When Xu You told Xu Chu that Cao Cao owed his conquest of Ji Province to him, Xu Chu insisted that it was the soldiers who were owed; Xu You then insulted Xu Chu, who ran him through and beheaded him. Cao Cao was angered with Xu Chu for killing his old friend and severely chastised him, and he then had Xu You buried with honors.

Meanwhile, Yuan Tan ravaged Ganling, Anping, Bohai, and Hejian and forced his brother to flee to Zhongshan. Yuan Tan, having gathered his father's old troops, decided to betray Cao Cao and retake Jizhou, so Cao Cao marched to Pingyuan, forcing Yuan Tan to beg Liu Biao for assistance. When Liu Biao refused, Yuan Tan fled Pingyuan for Nanpi, where he was besieged.